COVID-19

COVID-19 tests are available that can look for current infection or for past infection.

• A viral test can show if you have a current infection. There are two types of viral tests: nucleic acid amplification tests (NAATs) and antigen tests. These are swab or saliva tests. They are never blood tests.
• An antibody test (also known as a serology test) is a blood test. Antibody tests might tell you if you had an infection in the past but they cannot tell you when. They should not be used to test for a current infection. In addition, they cannot tell you if you are protected from getting COVID-19 now or in the future.

	VIRAL TESTS (swab or saliva tests) Looks for current infection		ANTIBODY TEST (blood tests) Looks for past infection
	NUCLEIC ACID AMPLIFICATION TEST (NAAT)	ANTIGEN TEST	ANTIBODY TEST
	Also known as molecular tests. Includes different types of tests such as: PCR (such as Reverse-Transcriptase Polymerase Chain Reaction - RT-PCR)  Loop-mediated isothermal amplification (LAMP)		Also known as blood test, serologic test, or “serology”
How the test works	Detects genetic material (RNA) within the COVID-19 virus	Detects proteins (or antigens) on the surface of the COVID-19 virus	Detects antibodies made by the immune system
How the test is done	Saliva, or swab from nose or throat	Swab from nose or throat	Blood from arm or finger stick
How long it takes to get results	Same day and up to 3 days. Some are rapid (around 20 minutes)	Most are rapid, around 15 minutes or less.	Same day and up to 3 days

There are 2 types of viral (swab or saliva) tests that are used to test for current COVID-19 infection – NAAT and antigen. Both types of test can be used for diagnostic testing and screening testing (see below). PCR tests are the best tests to look for current infection-they are a type of NAAT test that is usually performed in a laboratory.

• Antibody (blood) tests should not be used to look for current infection.
• Make sure you know what kind of test you are getting.

Diagnostic testing is used when there is reason to believe that the person has COVID-19 because they have symptoms and/or they know they were exposed. The purpose of the test is to find out if you are currently infected with the virus that causes COVID-19.

Diagnostic testing is recommended if:

•  You have COVID-19 symptoms: Talk to a doctor and get tested as soon as possible - even if you are fully vaccinated or have had COVID-19 in the past.
•  You have been a “close contact” to someone with COVID-19 within the last 14 days*:
  * If you have had a positive viral (swab or saliva) test for COVID-19 in the last 90 days, you do not need to get tested as long as you do not have symptoms of COVID-19.
• You are part of an outbreak investigation
  If you live or work in a place where other people have been diagnosed with COVID-19, you may need to be tested, even if you are fully vaccinated or had COVID-19 in the past.

Note: Both NAAT and antigen tests can be used for diagnostic testing, but antigen tests are more likely than NAATs to give a false negative result (meaning the test result is negative, but you actually have the infection).

See Understanding your viral test result and what to do next for more information.

“Screening testing” is when a person is tested for COVID-19 even though they do not have any signs or symptoms of COVID-19 and have not had contact with someone known to have COVID-19. Screening testing is used when it is important to find out if a person might be infected with the virus that causes COVID-19.

Except where listed below, screening testing is not recommended for fully vaccinated persons or for people who had a positive viral (swab or saliva) test in the last 90 days.

Screening testing is required if:

• You are not fully vaccinated, and
• You work in a place where COVID-19 vaccination is required.
• You are going to visit certain places, including mega-events, indoors at skilled nursing facilities, intermediate care facilities, and juvenile detention facilities, and indoors and outdoors at adult correctional and detention centers. Screening testing may also be required by certain businesses and venues.
• You are a staff member or athlete in moderate- or high-risk organized youth sports, including school sports teams. (Note: children under 12 years of age playing outdoor moderate- and high-risk sports are not required to test). See COVID-19 Prevention at Youth Sports for more details.
• You are traveling by plane into the United States from another country (even if you are fully vaccinated). See Requirement for Proof of Negative COVID-19 Test or Recovery from COVID-19 for All Air Passengers Arriving in the United States. Testing is also required before entering some other countries, check the rules before you plan your travel.

Note: There may be other settings that have their own screening testing requirements.

Screening testing is currently recommended:

• If you are NOT FULLY VACCINATED and
  • You participate in organized youth sports, including school sports teams. See Protocol for Organized Youth Sports for more details.
  • You are traveling outside of California (within the United States). Testing is recommended 1-3 days before and 3-5 days after travel. See Travel Advisory.
  • You are going to be attending an outdoor mega-event. (Testing will be required effective October 7, 2021)
• After returning from international travel, even if you are fully vaccinated
• For teachers and students in schools
  • It is recommended that students get regular screening testing if not fully vaccinated. (Unvaccinated teachers are required to get in regular screening testing).
  • If community transmission rates are high, fully vaccinated students and teachers may be asked to get tested as part of school surveillance testing

Note: Both NAAT and antigen tests can be used for screening testing. Antigen tests are often used because they are cheaper and provide fast results. But when they are used as a screening test, they are more likely to give a false positive result (meaning the test result is positive, but you don’t actually have the infection).

• If you have a positive antigen screening test, it is recommended that you get a NAAT test next to check that the result is correct. You must isolate while you wait for the NAAT result. See Understanding Your Viral Test Result and What to do Next for more information.

• From your doctor. If you need help finding a doctor, call 2-1-1 or visit 211LA
• At an LA County testing site – these sites offer free COVID-19 testing to anyone who lives in LA County, regardless of immigration status. Appointments are not always needed but are strongly encouraged to reduce wait times. Visit https://covid19.lacounty.gov/testing/ or call 2-1-1 to learn more.
• In a pharmacy. Many pharmacies offer free COVID-19 viral tests. Call or visit the website of your local pharmacy for details.
• At home. At-home collection kits and tests are available by prescription or over the counter in many locations. Visit the CDC self-testing website to learn more. Results of test kits collected and/or performed at home cannot be used to end quarantine early or to prove that you don’t have COVID-19.

Visit Community-Based Testing Sites for COVID-19 to locate no-cost testing at local health centers and select pharmacies.

Beware of COVID-19 testing scams – visit our COVID-19 scams and fraud page for more information.

• Health insurers are required (by federal law) to cover the entire cost of testing for the virus whether you have symptoms or not. A doctor will need to order the test. (Be aware that if you buy an at-home test without a prescription, your health insurance may not pay for it. Also, insurers are not required to cover COVID-19 testing if it is being done as part of an employee return-to-work programs.)
• Testing through LA County or LA City testing sites is free for all LA County residents who meet the criteria for testing. This includes undocumented residents or those with and without health insurance. Visit https://covid19.lacounty.gov/testing/.
• COVID-19 tests are available at no cost nationwide at health centers and select pharmacies. Visit Community-Based Testing Sites for COVID-19.

• Talk to your doctor about which test is right for you.
• If you have to be tested for screening purposes such as for work or travel, make sure that you get a test that meets the requirements of your employer, airline, or other institution.
• Before you get a test make sure that you know:
  • What type of test you are being offered (NAAT or antigen).
  • How long it will take to get your results.
  • How you will find out the results.
  • What precautions you should take while you wait for your results and what you should do if your result is positive or is negative.
• After you receive your test result, make sure that you understand what your result means and what to do next. You should be given a fact sheet about the test you received. If you did not, ask for one.

Talk with your doctor to make sure you understand what your viral test result means and any next steps.